Vapor-phase growing apparatus and vapor-phase growing method

1. A vapor-phase growing apparatus, comprising: a reactor containing a plurality of gas introduction portions and a gas reaction portion located below the gas introduction portions; a susceptor, of which a surface is exposed in an interior space of the gas reaction portion of the reactor, for disposing and fixing a substrate on the surface thereof; a gas distributor provided between the gas introduction portions and the gas reaction portion of the reactor; a plurality of gas inlet conduits which are connected with the gas introduction portions, respectively, the plurality of gas inlet conduits being disposed separately from each other; and a switching device, which is provided in an outside of the reactor, including a plurality of valves disposed upstream of each of the gas inlet conduits, each one of the plurality of valves being connected between a source of gas and a corresponding one of the gas inlet conduits to switch on or off the gas to be supplied to the corresponding gas inlet conduit, so that a number of the valves in an open state is controlled according to a volume of flow of the gas.

2. The apparatus as set forth in claim 1 , wherein the gas introduction portions are arranged in parallel with a direction of arrangement of gas supplying holes of the gas distributor.

3. The apparatus as set forth in claim 1 , wherein the carrier gas is at least one selected from the group consisting of nitrogen gas, hydrogen gas and argon gas.

4. A vapor-phase growing method, comprising: disposing and fixing a substrate on a susceptor, in a reactor containing a plurality of gas introduction portions, a gas reaction portion located below the gas introduction portions, and a plurality of gas inlet conduits connected with corresponding gas introduction portions, a surface of the susceptor being exposed in an interior space of the gas reaction portion of the reactor, and the plurality of gas inlet conduits being disposed separately from each other; supplying a gas at a first flow rate onto the substrate in the gas reaction portion from a first number of the gas inlet conduits to form a first film on the substrate; and supplying the gas at a second flow rate onto the substrate in the gas reaction portion from a second number of the gas inlet conduits to form a second film on the substrate.

5. The method as set forth in claim 4 , wherein the gas introduction portions are arranged in parallel with a direction of arrangement of gas supplying holes of the gas distributor.

6. The method as set forth in claim 4 , wherein the carrier gas is at least one selected from the group consisting of nitrogen gas, hydrogen gas and argon gas.

7. The vapor-phase growing apparatus as set forth in claim 1 , wherein the gas introduction portions include a first gas introduction portion and a second gas introduction portion, the gas distributor has a first gas supplying hole connecting the first gas introduction portion and the gas reaction portion, and a second gas supplying hole connecting the second gas introduction portion and the gas reaction portion, the gas inlet conduits include a first gas inlet conduit connected with the first gas introduction portion, and a second inlet conduit connected with the second gas introduction portion, and the switching device switches gases including an NH 3 raw material gas and a carrier gas to be supplied so that a first state and a second state is changed, in the first state, the NH 3 raw material gas is supplied to the first gas net conduit and the career gas is supplied to the second gas inlet conduit, and in the second state, the career gas is supplied to the first gas net conduit and the NH 3 raw material gas is supplied to the second gas net conduit.